Electric incandescent lamp

Abstract

The electric incandescent lamp has a filament (2) comprising light-emitting sections (5,6,7) and non-light-emitting sections (8,9) integral therewith. A non-light-emitting section (9) has at its two ends a helically wound portion (10,11), which portions are interconnected by the tungsten wire (3) from which the filament (2) is wound. An additional tungsten wire (14) extends along the non-light-emitting section (9) and is wound around each of its helically wound portions (10,11). The incandescent lamp has a filament (2) of a simple construction, whose manufacture can readily be mechanized.

What is claimed is: 
     
       1. An electric incandescent lamp comprising: a. an elongated, light transmissive envelope sealed in a vacuum tight manner;   b. first and second conductors extending through respective portions of the envelope;   c. a continuous tungsten wire filament extending longitudinally in the envelope from the first conductor to the second conductor, said filament forming at least first and second helically wound light-emitting sections and a non-light-emitting section for spacing apart said first and second light-emitting sections, said non-light-emitting section having first and second helically wound portions formed at opposite ends thereof;   d. an additional tungsten wire extending longitudinally in the envelope adjacent the non-light-emitting section and having first and second helically wound portions formed at opposite ends thereof, said helically wound portions being wound around the respective helically wound portions of said non-light-emitting section; and   e. means for supporting the filament in the envelope at said helically wound portions of the additional tungsten wire.   
     
     
       2. An electric incandescent lamp as in claim 1 where the means for supporting the filament in the envelope comprises a portion of at least one end of the additional tungsten wire which extends to an inner surface of the envelope.